Concerning the Planck scale (~ 1e18 GeV), we do not know. What we only start to know more about is the electroweak scale (~ 100 GeV) and the puzzle is however still not fully resolved (the Higgs boson is only one piece of it).

As you can see from the above numbers, there are many orders of magnitude between the electroweak and the Planck scales (which has by the way lead to the infamous hierarchy problem). Why such a hierarchy? We do not know. As a result and since this sounds very unnatural, we expect new phenomena to occur between these two scales. But maybe there is just nothing. This is why beyond the Standard Model physics is important today. We need to be prepared regarding any possible option that we will (or will not) discover.

Only (future) data will (hopefully) tell us :)

PS: the three-quark picture does not hold at the LHC. The proton is a much more complex dynamical object (you can check my last particle physics post for instance).